Error message while using Copy to Library

[BookJunkieLI]

I was using the Copy to Library (delete after copy) when I received the following error message:

calibre, version 9.16.0
ERROR: Unhandled exception: <b>CorruptError</b>:database disk image is malformed

calibre 9.16  embedded-python: True
Windows-11-10.0.26200-SP0 Windows ('64bit', 'WindowsPE')
('Windows', '11', '10.0.26200')
Python 3.14.8
Windows: ('11', '10.0.26200', 'SP0', 'Multiprocessor Free')
Interface language: None
EXE path: C:\Program Files\Calibre2\calibre.exe
Successfully initialized third party plugins: Gather KFX-ZIP (from KFX Input) (2, 34, 2) && DeDRM (10, 0, 9) && Package KFX (from KFX Input) (2, 34, 2) && AudioBook_Duration (1, 0, 9) && BookFusion Plugin (0, 8, 1) && CalibreSpy (1, 0, 92) && Consolidate All Library Metadata (2, 0, 46) && Count Pages (1, 15, 2) && EpubMerge (3, 3, 0) && EpubSplit (3, 12, 0) && FanFicFare (4, 60, 0) && Favourites Menu (1, 3, 2) && Find Duplicates (1, 10, 10) && Generate Cover (2, 4, 1) && Goodreads (1, 8, 5) && Import List (1, 9, 9) && Job Spy (1, 0, 239) && KFX metadata reader (from KFX Input) (2, 34, 2) && From KFX (2, 34, 2) && KFX Input (2, 34, 2) && Kindle Collections (1, 7, 29) && Kobo Utilities (2, 28, 2) && Manage Series (1, 5, 4) && Modify ePub (1, 8, 9) && MultiColumnSearch (1, 0, 96) && Quality Check (1, 14, 7) && Reading Goal (2, 1, 2) && Reading List (1, 15, 7) && Save Virtual Libraries To Column (2, 0, 1) && SmartEject (2, 6, 0) && View Manager (1, 10, 5)
Traceback (most recent call last):
  File "calibre\gui2\actions\copy_to_library.py", line 479, in copy_to_library
  File "calibre\gui2\actions\copy_to_library.py", line 559, in do_copy
  File "calibre\gui2\library\models.py", line 570, in delete_books_by_id
  File "calibre\db\cache.py", line 103, in call_func_with_lock
  File "calibre\db\cache.py", line 2770, in remove_books
  File "calibre\db\backend.py", line 2621, in remove_books
  File "calibre\db\backend.py", line 1375, in executemany
  File "C:\t\t\apsw-39uykmzm\src\cursor.c", line 223, in resetcursor
apsw.CorruptError: database disk image is malformed

Since I've never had this issue before, and "CorruptError: database disk image is malformed" doesn't sound good, I didn't want to do anything before running it by someone more knowledgeable. I'm guessing I need to restore database on the destination library but I haven't even tried opening it yet just in case.

I do suspect the root cause might be the unexpected shutdown of my computer at least once while running a previous Copy to Library from the original destination library that I'm now trying to copy back to. The unexpected shutdown was caused by power to the house being shutdown by power line work I hadn't known was happening.

[kovidgoyal]

The traceback shows the error happened in the "delete after copy" step, which runs against the library you are copying FROM (the currently open library), not the destination. So the copy itself most likely completed, and it is the source library's metadata.db that is damaged.

calibre has tools for exactly this, under Library maintenance. Click the arrow next to the calibre Library button in the toolbar, then Library maintenance:

1) First, as a precaution, close calibre and make a copy of the whole library folder (or at least of metadata.db in it).

2) Library maintenance->Check library. This runs an integrity check on the database and tries to repair it, then offers to check that the files on disk match the database. Often that is all you need.

3) If the check fails, use Library maintenance->Restore database. calibre keeps a backup of every book's metadata as a metadata.opf file in that book's folder, and this rebuilds metadata.db from those files. The old database is not deleted; it is renamed and kept in the library folder, and calibre tells you its name when the restore finishes. The OPF backups are written in the background, so a very recent metadata edit may not have made it into them yet. Otherwise your books, metadata and custom columns should all come back.

Once the source library is working again, the books you copied will still be in it, because the delete never happened. Check that they are present and fine in the destination library, then delete them from the source by hand.

[BookJunkieLI]

Thanks for getting back to me, Kovid.
The Check Database on the source library and the destination library both came back error free. Some "extra" titles to take care of but otherwise all good.

Thanks again.